Protein Intakes Above the Recommended Dietary Allowance Reduce Fat Mass Irrespective of Energy Balance and Resistance Training Status: A Systematic Review and Meta-analysis (P08-056-19)

Abstract

ObjectivesThe recommended dietary allowance (RDA) for protein of 0.8 g/kg/d is the current standard of dietary adequacy. Research assessing the effects of higher protein intakes on body composition often focus on changes in lean mass and use the RDA as the reference protein intake. However, it is important to also assess the importance of protein intake on fat mass, which relates to cardiometabolic health indices. Therefore, we sought to conduct a systematic review and meta-analysis to determine the effects of protein intakes greater than versus at the RDA on changes in whole body fat mass. MethodsThree researchers independently screened 1531 articles published through August 2018 using PubMed, Scopus, CINAHL, and Cochrane databases, with additional articles identified through previously published review articles. Randomized-controlled, parallel studies at least 6 weeks long on apparently healthy adults (> = 19 years old) were eligible for data extraction. ResultsData from 16 randomized-controlled, parallel studies resulting in 20 comparisons of fat mass changes were included in the final analysis. This abstract presents sub-analyses for comparisons with catabolic and anabolic stimuli, specifically energy restriction (ER) and/or resistance training (RT), respectively. Among all comparisons, consuming greater than the protein RDA resulted in greater fat mass change [–0.81 kg (–1.25, –0.37); WMD (95% CI), n = 20 comparisons]. The beneficial effect of greater protein intake on adiposity was apparent irrespective of energy or training status. Groups consuming greater than the RDA with ER lost more fat mass [–0.91 kg (–1.55, –0.28), n = 13], and groups consuming greater than the RDA without ER lost fat mass, while there was no reduction in groups consuming the RDA [–0.65 kg (–1.29, –0.05), n = 7]. Greater protein intake promoted fat mass loss with RT [–0.91 kg (–1.55, –0.28), n = 2] and without RT [–0.65 kg (–1.29, –0.05), n = 18]. ConclusionsThese results support protein intakes greater than the RDA to reduce fat mass, irrespective of energy balance and resistance training status. Funding SourcesNo external funding was provided.